Permeable impact-resistant distribution dam suitable for confluence of natural main river channel and natural branch river channel

The invention discloses a permeable impact-resistant distribution dam suitable for the confluence of a natural main river channel and a natural branch river channel. The permeable impact-resistant distribution dam comprises a dam body which is arranged between two opposite banks at the confluence of the main and branch river channels along trend lines of the branch river channel. The dam body is composed of a middle dam body section, a left dam body section and a right dam body section, the middle dam body section is arranged longitudinally, the cross section of the middle dam body section is of a trapezoidal structure, and the left dam body section and the right dam body section are connected on the left side and the right side of the middle dam body longitudinally. The middle dam body section is of a rock-fill dam structure composed of stone, and each of the left dam body section and the right dam body section is of a gabion dam body structure composed of a gabion. A control, guide and distribution structure is adopted, the permeable impact-resistant distribution dam is arranged between shore-bank slopes at the confluence of the natural main and branch river channels, river streaming potential is improved, silting at the river channel confluence is reduced, and river regime is in a favorable form; the permeable impact-resistant distribution dam is good in structural integrity, high in impact resistance, low in requirements on topographic and geological conditions; a permeable structure is adopted, water pressure on two sides is balanced, and structural stability performance is good.